I believe only front wheel drive cars have CV boots. CV stands for "Constant Velocity" as in the joint at the front wheels that allows them to move while still transferring power from the transaxle to the from wheels. It does the same thing a U-joint does for your driveshaft ona a rear wheel drive car but in a slightly different manner. Because of the way they work they have boots surounding them to hold the grease in. U-joints dont have the boot.